Sodium Bicarbonate: Uses, Side Effects & Contraindications

Flávia Costa
Clinical review: Flávia Costa Pharmacist
Created by: Tua Saude editing team

Sodium bicarbonate (also known as baking soda) is an alkaline compound that can be used to help whiten teeth, ease heartburn and acid reflux, soothe an itchy throat, and help prepare and sanitize foods.

Sodium bicarbonate works by helping reduce alkalinity or acidity, which is why it can be used for different everyday purposes. However, when used incorrectly, it can harm the skin and cause problems like irritation or redness.

It is important to consult a healthcare provider before using sodium bicarbonate or if you experience irritation or redness where it’s applied. They can recommend the most appropriate amount for you based on its intended use.

woman spooning a large spoonful of sodium bicarbonate out of a jar

Indications for use

Sodium bicarbonate may be recommended to:

1. Whiten teeth

Using toothpaste that contains sodium bicarbonate is one way to deeply clean the teeth and gums.

This is because it can help remove yellow discoloration from stains on tooth enamel and reduce bacterial plaque that tends to build up in areas the toothbrush does not reach as well.

How to use: it is recommended to brush your teeth with a sodium bicarbonate toothpaste 2 to 3 times per day.

2. Ease heartburn and reflux

Sodium bicarbonate can help reduce burning and pain after meals caused by stomach acidity and reflux, because it helps neutralize stomach acids.

How to use: dissolve ½ teaspoon of sodium bicarbonate in 250 mL of water. Drink at least half of the solution to help relieve burning and pain, particularly after meals.

Use of sodium bicarbonate should not exceed 1 ½ teaspoons per day, and it should be used for no longer than 2 weeks.

3. Exfoliate and reduce foot odor

A sodium bicarbonate scrub can help remove dead skin cells in thicker, rougher areas of the feet, such as the heels and soles.

In addition, sodium bicarbonate is a strong odor neutralizer due to its antibacterial action and may help reduce foot odor.

How to use: mix ½ teaspoon of sodium bicarbonate with 2 tablespoons of liquid soap or sweet almond oil, and apply to the feet using circular motions for 10 minutes.

Then wash with warm or cool water and dry with a soft towel.

Also recommended: Sugar Scrubs (and Other Natural Exfoliant Recipes to Make at Home) tuasaude.com/en/sugar-scrub

4. Sitz bath for UTI symptoms

A sitz bath with sodium bicarbonate may help relieve symptoms such as urinary urgency, pain, and burning, and can be a good way to complement medical treatment with antibiotics.

In addition, a sodium bicarbonate sitz bath may be used for cytolytic vaginosis, for example.

How to use: to help with urinary tract infection (UTI) symptoms, fill a basin with 3 liters of water and add 3 tablespoons of sodium bicarbonate, stirring until it dissolves completely.

Then sit in the water for about 20 to 30 minutes. It can be repeated once a day.

For cytolytic vaginosis, it is recommended to do the sitz bath up to 2 times per day, once a month, or as advised by a gynecologist.

5. Reduce dark spots on the skin

Exfoliating the skin with sodium bicarbonate can help remove dead skin cells and stimulate new cell production, which may help lighten dark spots on the skin.

How to use: mix 1 teaspoon of sodium bicarbonate into 3 tablespoons of sweet almond oil or coconut oil until you get a smooth mixture.

Massage the area in circular motions for 10 minutes and rinse with warm water until all residue is removed. 

Use this scrub once per week, or as advised by a healthcare provider, since it may cause skin irritation.

6. Deep-clean hair

The small granules of sodium bicarbonate can act as an exfoliant and may help remove excess scalp oil and seborrheic dandruff.

It helps open the hair cuticles, allowing ingredients from creams and conditioning masks (such as hair-sealing treatments) to penetrate more easily.

How to use: mix 1 to 2 tablespoons of sodium bicarbonate with a small amount of water until it forms a paste.

Apply to the scalp and hair, leave on for 15 minutes, then rinse. Afterward, wash your hair with your usual shampoo.

7. Whiten nails

Sodium bicarbonate can help reduce yellow discoloration on the nails and may help strengthen nail growth.

How to use: mix ½ teaspoon of sodium bicarbonate with 2 tablespoons of water and rub the mixture onto each nail using gauze or cotton. Leave it on for 5 minutes, then rinse the nails under running water.

8. Exfoliate skin before hair removal

Removing dead skin cells from the top layer of the skin helps natural ingredients penetrate and may help make hair removal more effective and less painful.

How to use: mix 1 ½ teaspoons of sodium bicarbonate with water or coconut oil and apply to the skin using gentle circular motions for 10 minutes, avoiding vigorous scrubbing to prevent skin injury.

Next, rinse the area with warm or cool water and dry with a soft towel. For best results, exfoliate 1 day before hair removal.

9. Gargle for an itchy throat

An itchy throat can be caused by factors such as allergies, irritation, or infection.

In this case, sodium bicarbonate may help reduce microorganisms present in the area.

How to use: mix 1 tablespoon of sodium bicarbonate in half a glass of warm water and gargle. Repeat the process 4 to 5 times.

10. Sanitize foods

Sodium bicarbonate can help reduce or eliminate certain viruses and bacteria on foods that may cause illnesses like hepatitis, cholera, or salmonella.

It can also help remove dirt, along with certain agricultural chemicals and pesticides, from fruits and vegetables that have peels or from leafy greens.

How to use: soak foods in a container with 1 liter of water and 1 tablespoon of sodium bicarbonate for about 15 minutes. Then rinse under running water to remove residue before eating.

11. Improve exercise performance

Sodium bicarbonate can be used as a as a pre-exercise supplement to improve performance and strength during physical activity, especially high-intensity exercise in athletes.

It may also help speed up recovery and reduce muscle fatigue.

How to use: the usual recommended dose is 300 mg of sodium bicarbonate per kg of body weight, added to a glass of water or unsweetened natural fruit juice, taken 1 to 2 hours before exercise.

However, sodium bicarbonate as a pre-workout supplement should only be used under medical or dietitian guidance, based on the type of training and overall health status.

12. Help relieve symptoms from a bee sting

Sodium bicarbonate may help neutralize venom from a bee or wasp sting, which can reduce symptoms such as swelling, pain, or redness at the sting site.

How to use: mix 3 teaspoons of sodium bicarbonate with 1 teaspoon of filtered water until it forms a paste. Then apply it to the bee or wasp sting after removing the stinger, leaving it on for 10 to 15 minutes. Rinse afterward.

13. Help relieve symptoms from a vaginal infection

Sodium bicarbonate may also be used in sitz baths to help relieve symptoms associated with a vaginal infection, such as itching and burning, and to help balance vaginal pH.

How to use: add 1 tablespoon of sodium bicarbonate to 1 liter of warm water. Sit in the basin for 15 to 20 minutes, at least 2 times per day.

Side effects

The most common side effects of oral sodium bicarbonate include:

  • Headache;

  • Muscle pain and spasms;

  • Nausea and vomiting;

  • Slower breathing;

  • Nervousness or restlessness;

  • Unpleasant taste in the mouth.

In addition, sodium bicarbonate use can cause metabolic alkalosis, abdominal cramps, increased thirst, and a stronger urge to urinate.

Sodium bicarbonate can also cause a severe allergic reaction or anaphylaxis, which requires immediate medical attention at the emergency department. 

When sodium bicarbonate is applied to the skin, it may cause redness and irritation in some people.

Contraindications for use

Oral sodium bicarbonate should not be used by children under 2 years old or by people who are pregnant or breastfeeding.

It is also contraindicated for people with low blood calcium levels, decreased stomach hydrochloric acid production (hypochlorhydria), or metabolic or respiratory alkalosis.

Sodium bicarbonate can interact with other medications, so it is important to talk to a doctor before starting use.

Oral or topical sodium bicarbonate is contraindicated for people who are allergic to this substance.

Update History
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References
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